US10570495B2 - Surface layer for fast diffusion and method to produce thereof - Google Patents
Surface layer for fast diffusion and method to produce thereof Download PDFInfo
- Publication number
- US10570495B2 US10570495B2 US15/563,716 US201515563716A US10570495B2 US 10570495 B2 US10570495 B2 US 10570495B2 US 201515563716 A US201515563716 A US 201515563716A US 10570495 B2 US10570495 B2 US 10570495B2
- Authority
- US
- United States
- Prior art keywords
- work surface
- working part
- friction work
- friction
- laser shock
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related, expires
Links
- 238000000034 method Methods 0.000 title claims abstract description 101
- 238000009792 diffusion process Methods 0.000 title claims abstract description 15
- 239000002344 surface layer Substances 0.000 title 1
- 230000035939 shock Effects 0.000 claims abstract description 46
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 14
- 125000004433 nitrogen atom Chemical group N* 0.000 claims abstract description 13
- 238000003754 machining Methods 0.000 claims description 13
- 229910001018 Cast iron Inorganic materials 0.000 claims description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000005255 carburizing Methods 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000005480 shot peening Methods 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/02—Pretreatment of the material to be coated
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D10/00—Modifying the physical properties by methods other than heat treatment or deformation
- C21D10/005—Modifying the physical properties by methods other than heat treatment or deformation by laser shock processing
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
- C23C8/28—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases more than one element being applied in one step
- C23C8/30—Carbo-nitriding
- C23C8/32—Carbo-nitriding of ferrous surfaces
Definitions
- the field to which the disclosure generally relates includes ferritic nitrocarburizing processes.
- Ferritic nitrocarburizing processes utilize a furnace treatment for a predetermined amount of time in order to diffuse carbon and nitrogen into the surface of a part. Preparing the surface of a part prior to heat treatment may increase or decrease the diffusion rate on the surface of the part.
- a number of variations may include a method that may include laser shock peening a friction work surface of a working part and may include applying a ferritic nitrocarburizing process to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface may be accelerated.
- a number of variations may include a method that may include machining a friction work surface of a working part; laser shock peening the friction work surface; and applying a ferritic nitrocarburizing process to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface may be accelerated.
- a number of variations may include a method that may include applying a stress relief treatment to the working part at a temperature ranging from about 610° C. for 3 hours; machining a friction work surface of a working part; laser shock peening the friction work surface utilizing a high power density laser having a power of about 1 GW/cm 2 including a pulse energy of about 3 Joules, pulse duration of about 20 nanoseconds, and a laser beam diameter of about 3 mm; and applying a ferritic nitrocarburizing process to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface may be accelerated.
- a number of variations may include a method that may include machining a friction work surface of a working part; laser shock peening the friction work surface utilizing a high power density laser having a power greater than or equal to 1 GW/cm 2 including a pulse energy of about 3 Joules, pulse duration of about 20 nanoseconds, and a laser beam diameter of about 3 mm; and applying a ferritic nitrocarburizing process for about 8 to about 12 hours at about 465° C. to about 495° C. to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface may be accelerated.
- a number of variations may include a product that may include a part that may include a friction working surface that has been cast, undergone a stress relief process at about 610° C. for about 3 hours, machined, and a laser shock peened amorphous layer disposed on the friction working surface wherein the amorphous layer ranges from about 5 microns to about 500 microns in depth.
- a number of variations may include a product that may include a part that may include a friction working surface that has been cast, machined, laser shock peened, and treated with a ferritic nitrocarburizing process ranging from about 555° C. to about 585° C. for about 1 to about 3 hours and an amorphous layer disposed on the friction working surface wherein the amorphous layer ranges from about 5 microns to about 500 microns in depth.
- FIG. 1 depicts one variation of a cast iron brake rotor
- FIG. 2 depicts one variation of a part that may include a friction working surface.
- a working part such as a brake disc or drum brake, may have a friction working surface.
- the working part may include cast iron.
- the friction working surface may undergo a ferritic nitrocarburizing process involving a heat treatment step for a predetermined amount of time. Prior to undergoing the ferritic nitrocarburizing process, the friction working surface may undergo a surface treatment such as machining, shot peening, or cold working. Alternatively, the friction working surface may undergo a laser shock peening or laser shock peening process to form a nanocrystalline layer or amorphous layer on the surface of the working part.
- a nanocrystalline layer may have grain sizes ranging from about 5 nm to about 1000 nm.
- An amorphous layer may have an amorphous structure. The nanocrystalline layer or amorphous layer may range from about 5 to about 500 microns in depth.
- the laser shock peening process may utilize a laser having a pulse energy of 3 Joules and a pulse duration of 20 nanoseconds.
- the diameter of the laser beam may be about 3 millimeters.
- the scan frequency of the laser shock peening process may be about 2 Hz.
- the working part may undergo a ferritic nitrocarburizing process at a temperature ranging from about 570° C. to about 580° C. for about 1 to about 3 hours or from about 465° C. to about 495° C. for about 2-10 hours to achieve a compound layer about 10 microns in depth.
- One process may include casting an iron brake drum or disk, stress relieving the brake at 610° C. for 3 or more hours, machining the friction working surface of the brake, laser shock peening the friction working surface, and nitro-carburizing the brake at 570° C. for about 1 hour or at a temperature ranging from about 555° C. to about 585° C. for about 2-5 hours.
- One process may include casting an iron brake drum or disk, machining the friction working surface of the brake, laser shock peening the friction working surface and nitro-carburizing the brake at 480° C. for about 8 to about 10 hours.
- a number of variations may include a product that may include a part 10 that may include a friction working surface 12 that has been cast, undergone a stress relief process at about 610° C. for about 3 hours, machined, and a laser shock peened amorphous layer 14 disposed on the friction working surface 12 wherein the amorphous layer 14 ranges from about 5 microns to about 500 microns in depth.
- a method may include laser shock peening a friction work surface of a working part and may include applying a ferritic nitrocarburizing process to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface is accelerated.
- Variation 2 may include a method as set forth in variation 1 wherein the laser shock peening process may refine the microstructure of the friction work surface such that a nanocrystalline layer of about 5 to about 500 ⁇ m in depth is formed.
- Variation 3 may include a method as set forth in variation 1 or 2 wherein the laser shock peening process refines the microstructure of the friction work surface such that an amorphous layer of less than or equal to about 500 ⁇ m in depth is formed.
- Variation 4 may include a method as set forth in any of variations 1 through 3 wherein the laser shock peening process utilizes a high power density laser having a power ranging from about 0.5 GW/cm 2 to about 5 GW/cm 2 .
- Variation 5 may include a method as set forth in any of variations 1 through 4 wherein the ferritic nitrocarburizing process may include a furnace treatment for about 2-6 hours at about 555° C. to about 585° C.
- Variation 6 may include a method as set forth in any of variations 1 through 5 wherein the ferritic nitrocarburizing process may include a furnace treatment for about 2-4 hours at about 570° C.-580° C.
- Variation 7 may include a method as set forth in any of variations 1 through 6 wherein the laser shock peening process includes a pulse energy of about 3 Joules, pulse duration of about 20 nanoseconds, and a laser beam diameter of about 3 mm.
- Variation 8 may include a method as set forth in any of variations 1 through 7 and may further include, prior to laser shock peening the friction work surface, applying a stress relief treatment to the working part at about 610° C. for about 2-4 hours.
- Variation 9 may include a method as set forth in any of variations 1 through 8 further may include, prior to laser shock peening the friction work surface, machining the friction work surface.
- a method may include machining a friction work surface of a working part; laser shock peening the friction work surface; and applying a ferritic nitrocarburizing process to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface may be accelerated.
- Variation 11 may include a method as set forth in variation 10 wherein the ferritic nitrocarburizing process may include a furnace treatment for about 8 to about 12 hours at about 455° C. to about 495° C.
- Variation 12 may include a method as set forth in any of variations 10 through 11 wherein the laser shock peening process refines the microstructure of the friction work surface such that a nanocrystalline layer of about 5 to about 500 ⁇ m in depth is formed.
- Variation 13 may include a method as set forth in any of variations 10 through 12 wherein the laser shock peening process refines the microstructure of the friction work surface such that an amorphous layer is formed.
- Variation 14 may include a method as set forth in any of variations 10 through 13 wherein the laser shock peening process utilizes a high power density laser having a power ranging from about 0.5 GW/cm 2 to about 5 GW/cm 2 .
- Variation 15 may include a method as set forth in any of variations 10 through 14 wherein the laser shock peening process includes a pulse energy of about 3 Joules, pulse duration of about 20 nanoseconds, and a laser beam diameter of about 3 mm.
- Variation 16 may include a method as set forth in any of variations 10 through 15 may further include, prior to laser shock peening the friction work surface, applying a stress relief treatment to the working part at about 610° C. for greater than or equal to about 3 hours.
- a method may include applying a stress relief treatment to the working part at about 610° C. for 3 hours; machining a friction work surface of a working part; laser shock peening the friction work surface utilizing a high power density laser having a power of about 1 GW/cm 2 including a pulse energy of about 3 Joules, pulse duration of about 20 nanoseconds, and a laser beam diameter of about 3 mm; and applying a ferritic nitrocarburizing process to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface may be accelerated.
- Variation 18 may include a method as set forth in variation 17 wherein the ferritic nitrocarburizing process may include a furnace treatment ranging from about 1 to about 3 hours at about 555° C. to about 585° C.
- Variation 19 may include a method as set forth in any of variations 17 through 18 wherein the ferritic nitrocarburizing process may include a furnace treatment ranging from about 8 to about 12 hours at about 465° C. to about 495° C.
- a method may include laser shock peening a friction work surface of a working part utilizing a high power density laser having a power greater than or equal to 1 GW/cm 2 including a pulse energy of about 3 Joules, pulse duration of about 20 nanoseconds, and a laser beam diameter of about 3 mm; and applying a ferritic nitrocarburizing process for about 8 to about 12 hours at about 465° C. to about 495° C. to the friction work surface such that diffusion of carbon and nitrogen atoms into the friction work surface may be accelerated.
- a product may include a part that may include a friction working surface that has been cast, undergone a stress relief process at about 610° C. for about 3 hours, machined, and a laser shock peened and an amorphous layer disposed on the friction working surface wherein the amorphous layer ranges from about 5 microns to about 500 microns in depth.
- Variation 22 may include a product as set forth in variation 21 wherein the part is a cast iron brake rotor.
- a product may include a part may include a friction working surface that has been cast, machined, laser shock peened, and treated with a ferritic nitrocarburizing process at about 450° C. for about 2 to about 4 hours and an amorphous layer disposed on the friction working surface wherein the amorphous layer ranges from about 5 microns to about 500 microns in depth.
- Variation 24 may include a product as set forth in variation 23 wherein the part is a cast iron brake rotor.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Thermal Sciences (AREA)
- Optics & Photonics (AREA)
- Crystallography & Structural Chemistry (AREA)
- Laser Beam Processing (AREA)
- Braking Arrangements (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
Description
Claims (21)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US2015/024822 WO2016164003A1 (en) | 2015-04-08 | 2015-04-08 | Surface layer for fast diffusion and method to produce thereof |
Publications (2)
Publication Number | Publication Date |
---|---|
US20180073122A1 US20180073122A1 (en) | 2018-03-15 |
US10570495B2 true US10570495B2 (en) | 2020-02-25 |
Family
ID=57072823
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US15/563,716 Expired - Fee Related US10570495B2 (en) | 2015-04-08 | 2015-04-08 | Surface layer for fast diffusion and method to produce thereof |
Country Status (4)
Country | Link |
---|---|
US (1) | US10570495B2 (en) |
CN (1) | CN107484420A (en) |
DE (1) | DE112015006265T5 (en) |
WO (1) | WO2016164003A1 (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20220298644A1 (en) * | 2019-08-30 | 2022-09-22 | Ab Sandvik Coromant | Method of treating a coated cutting tool |
CN112144010A (en) * | 2020-09-28 | 2020-12-29 | 江苏大学 | Process for improving performance of carbonitriding layer through laser shock strengthening |
CN112647083A (en) * | 2020-11-24 | 2021-04-13 | 江苏大学 | Alloy steel surface composite strengthening process |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6153023A (en) | 1996-07-12 | 2000-11-28 | Sintokogio, Ltd. | Hardened metal product produced by shot peening with shot having high hardness |
US20080000550A1 (en) | 2006-06-29 | 2008-01-03 | Gm Global Technology Operations, Inc. | Salt Bath Ferritic Nitrocarburizing of Brake Rotors |
US20110220415A1 (en) | 2009-08-18 | 2011-09-15 | Exxonmobil Research And Engineering Company | Ultra-low friction coatings for drill stem assemblies |
CN103046058A (en) | 2013-01-25 | 2013-04-17 | 山东大学 | Method for realizing nitriding or carburizing by thermal airflow jetting heating and shot blasting |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110079326A1 (en) * | 2009-10-07 | 2011-04-07 | Gm Global Technology Operations, Inc. | Method to increase corrosion resistance in ferritic nitrocarburized treated cast iron substrates |
-
2015
- 2015-04-08 WO PCT/US2015/024822 patent/WO2016164003A1/en active Application Filing
- 2015-04-08 CN CN201580078658.7A patent/CN107484420A/en active Pending
- 2015-04-08 US US15/563,716 patent/US10570495B2/en not_active Expired - Fee Related
- 2015-04-08 DE DE112015006265.3T patent/DE112015006265T5/en not_active Withdrawn
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6153023A (en) | 1996-07-12 | 2000-11-28 | Sintokogio, Ltd. | Hardened metal product produced by shot peening with shot having high hardness |
US20080000550A1 (en) | 2006-06-29 | 2008-01-03 | Gm Global Technology Operations, Inc. | Salt Bath Ferritic Nitrocarburizing of Brake Rotors |
US20110220415A1 (en) | 2009-08-18 | 2011-09-15 | Exxonmobil Research And Engineering Company | Ultra-low friction coatings for drill stem assemblies |
CN103046058A (en) | 2013-01-25 | 2013-04-17 | 山东大学 | Method for realizing nitriding or carburizing by thermal airflow jetting heating and shot blasting |
Non-Patent Citations (2)
Title |
---|
B.K. Pant, V. Arya, and B.S. Mann, Cavitation Erosion Characteristics of Nitrocarburised and HPDL Treated Martensitic Stainless Steels, J. Mater. Eng. Perform., 2012, 21(6), p. 1051-1055. * |
Improvement of wear resistance by laser shock processing and carburization composition technology used on 12crNi3A steel, Li Jing, et al. vol. 26, No. 5 dated May, 2014. |
Also Published As
Publication number | Publication date |
---|---|
DE112015006265T5 (en) | 2017-11-30 |
CN107484420A (en) | 2017-12-15 |
WO2016164003A1 (en) | 2016-10-13 |
US20180073122A1 (en) | 2018-03-15 |
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